Project consists of multiple correlations of the following parameters: Study of the visco-elastic properties of the bladder wall strips and clinical rapid cystometry, measurement of maximum isometric intravesical pressure during micturition studies using the stop-flow technique, uroflowmetry, measurement of bladder neck and urethral passive resistance, (compliance) as an index of obstruction, the determination of detrusor and vesical neck collagen content and of collagen enzymatic activity, electromicroscopy of the bladder wall and vesical neck in surgical specimens, electrophysiological studies of the contractility of muscle strips in vitro. Correlation between clinical tests done in these patients with biochemical, morphological and physiological changes studied in biopsy should allow for a better understanding of the effect of prostatic obstruction on the bladder wall. Also physiological classification of congenital bladder acontractility will be attempted since the same methods can be applied providing the clinical material becomes available. This project is aimed at anwering the following questions - (1) What is the optimal time to do a prostatectomy before irreversible bladder changes occur, (2) How to measure vesical neck and urethral compliance with accuracy through improved methods, (3) What is the exact relationship between viscoelastic coefficients variation and collagen content of muscle in the bladder and vesical neck, (4) How to classify congenital detrusor acontractility in children, (5) When should a vesical neck be resected or enlarged in children with urinary dysfunction.